Scrub Sponge

ABSTRACT

A scrub sponge includes a soft polyester foam sponge and a reticulated polyurethane foam scrub layer. The scrub layer is fused to the sponge entirely around their registered peripheries and at a plurality of locations between the peripheries. The fusing of the scrub layer to the sponge defines a pattern of recesses in the scrub layer. The recesses are effective for accumulating and trapping debris removed by the scrub layer. The debris then can be separated efficiently from the sponge by normal rinsing.

[0001] This application claims priority on U.S. Provisional Patent Appl. No. 60/372,191, filed Apr. 11, 2002.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The invention relates to a scrub sponge that can be used to scrub and clean surfaces without scratching.

[0004] 2. Description of the Related Art

[0005] Scrub sponges typically include a sponge and an abrasive layer adhered to one surface of the sponge. The sponge typically is formed from a synthetic material and functions to retain water or a solution of water and soap. The abrasive layer typically is formed from a non-woven array of synthetic fibers and typically does not retain water. Rather, the abrasive layer functions to engage debris on a surface that requires cleaning. Movement of the abrasive layer over the surface disengages the debris. Simultaneously, the water or water/soap solution in the sponge passes through the abrasive layer and cleans the surface over which the abrasive layer is rubbed.

[0006] Scrub sponges, as described above, typically are less abrasive than steel wool pads. Hence, scrub sponges often are recommended for use with surfaces that are prone to scratching, such as various specially coated non-stick cookware, ceramic bake ware, copper, stainless steel, glass, porcelain, Formica, Corian, cabinets and the like. It has been found, however, that most scrub sponges abrade many of the above-described surfaces after a short term of use. Thus, small unsightly scratches will appear on the surfaces after being subjected to cleansing with most prior art scrub sponges. The scratches become more evident over time and often begin to trap small particles of debris, hence leading to a surface discoloration and affecting appearance. Most people address the surface discoloration by scrubbing harder, thereby further degrading the surface. In a similar manner, frequent use of most prior art scrub sponges will degrade the performance of specialty non-stick surfaces on cookware.

[0007] In view of the above, an object of the subject invention is to provide a scrub sponge that substantially reduces the abrasion characteristics of the sponge.

[0008] Another object of the subject invention is to provide a scrub sponge that provides high quality cleaning capabilities.

[0009] A further object of the subject invention is to provide a scrub sponge that substantially avoids manufacturing complications and compromises relating to the requirement for carefully selecting adhesives that are compatible with both the sponge and the abrasive material.

SUMMARY OF THE INVENTION

[0010] The subject invention is directed to a scrub sponge that comprises a soft flexible sponge and a scrubbing layer with sufficiently low abrasive characteristics to prevent damage to the surfaces being cleaned. The scrub sponge includes a sponge formed from a very soft polyester foam. The scrubbing layer is formed from a reticulated filter foam, such as a reticulated polyurethane or polyether. The scrub layer is secured to the sponge by heat sealing. More particularly, selected regions of the scrub layer are subjected to heat and pressure sufficient to cause local fusing of the scrub layer to adjacent surface regions of the sponge. The heat sealing or fusing preferably is carried out in narrow lines that extend around the perimeter of the scrub layer and at selected locations within the perimeter. A preferred pattern of heat sealing lines, as explained below, forms a grid pattern on the scrub layer. However, parallel lines or a pattern of curved lines could provide comparable effectiveness. The heat sealing causes local surface discontinuities in the scrub layer that can resemble a quilting pattern with bulges between heat sealed regions. The surface discontinuities contribute to the ability of the scrub layer to engage, remove and collect debris from a surface that is being, cleaned without increasing abrasiveness of the scrub layer.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011]FIG. 1 is a perspective view of a scrub sponge in accordance with the subject invention.

[0012]FIG. 2 is a bottom plan view of the scrub sponge showing the scrub layer thereof..

[0013]FIG. 3 is a front elevational view.

[0014]FIG. 4 is a side elevational view.

[0015]FIG. 5 is a cross-sectional view.

[0016]FIG. 6 is a top plan view.

[0017]FIG. 7 is a front elevational view of the alternate embodiment.

[0018]FIG. 8 is a top plan view of an alternate embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0019] A scrub sponge in accordance with the subject invention is identified generally by the numeral 10 in FIGS. 1-6. The scrub sponge 10 includes a generally rectangular sponge 12 and a scrub layer 14. In the illustrated embodiment, the scrub sponge 10 includes proximally equal lengths and widths and rounded corners. However, other configurations are possible. Additionally, various colors and color combinations can be provided for the sponge 12 and the scrub layer 14.

[0020] The sponge 12 is formed from a very soft polyester foamed material that will absorb and retain water or a water soap solution. The sponge 12 makes up the major portion of the volume of the scrub sponge 10, as illustrated most clearly in FIG. 5.

[0021] The scrub layer 14 is formed from a reticulated filter foam, such as a reticulated polyurethane foam. The polyurethane foam becomes reticulated by being subject to heat and pressure within a closed environment. The combination of heat and pressure converts the foam into a flexible skeletal foam structure without cell membranes, and hence defining an open-pore foam. Reticulated foams can be fabricated easily to any desired size and shape and exhibit desirable chemical resistance, high tensile strength and desirable elongation and tear properties when subjected to typical forces encountered by a scrub sponge. A reticulated polyurethane foam also is impervious to microbial organisms. One preferred scrub layer is formed from a reticulated polyether foam. Polyether foams are not attacked by acids and alkalis and are hydrolytically stable. The specific characteristics of the scrub layer can be varied in accordance with various intended applications. However, a preferred polyether reticulated foam is formed to provide approximately 20-30 pores per inch and a density of approximately 1.4 lb./cu.ft. Tensile strengths of foams of this type are found to be in the range of approximately 18-20 psi and exhibit a tear strength of approximately 5.0 lb./inch. Reticulated foams are available from Crest Foam.

[0022] The combination of the very soft polyester sponge 12 and the reticulated polyurethane foam 14, as described above, is particularly desirable in view of similar melt characteristics for both materials. Thus, the reticulated filter foam of the scrub layer 14 can be fused to the soft polyester foam of the sponge 12 by heat sealing. The heat sealing is carried out by applying heat and pressure to specified regions of the scrub layer 14. As shown most clearly in FIG. 2, heat sealing is carried out entirely around the periphery of the scrub sponge 10 to define a fused peripheral seam 16 where the scrub layer 14 and the sponge 12 are secured integrally to one another. The peripheral seam 16 extends inwardly for a distance of approximately 0.08-0.15 inch. The heat sealing also is carried out to provide fusing at a plurality of interior locations. A preferred fusing pattern defines a grid as illustrated most clearly in FIG. 2. The grid includes a first plurality of parallel interior heat sealed lines 18 and a second plurality of parallel heat sealed lines 20, with the heat sealed lines in the first and second pluralities 18 and 20 intersecting one another. Additionally, each of the interior heat sealed lines 18, 20 extend to and intersect the peripheral heat sealed seam 16. Thus, the scrub layer 14 is secured integrally to the sponge 12 at a plurality of locations interiorly of the peripheral seam 16 of the scrub sponge 10.

[0023] The heat sealing of the scrub layer 14 to the sponge 12 at the plurality of interior locations create a plurality of surface irregularities or undulations as shown most clearly in FIGS. 1 and 3-5. The surface irregularities or undulations create peaks identified generally by the numeral 22 and valleys 24. The peaks 22 contribute to a major portion of the low abrasive scrubbing of the scrub sponge 10. However, the valleys 24 and the overall pattern of surface irregularities or undulations contributes to scrubbing effectiveness, with the valleys 24 defining regions for trapping and retaining debris removed from a surface that is being cleaned by the sponge 10.

[0024] An optional embodiment of the scrub sponge further includes a hand strap 26 that extends across the exposed surface of the sponge 12 from one peripheral region to another, as shown in FIGS. 7 and 8. The hand strap 26 is secured into position by the heat sealing and may provide a convenient means for gripping the scrub sponge 10 and retaining the sponge on the four fingers of the cleaning hand. However, the hand strap 26 is not required.

[0025] While the invention has been described with respect to certain preferred embodiments, it is apparent that various changes can be made without departing from the scope of the invention. In particular, the scrub layer can be formed from a broad range of densities of reticulated foam in accordance with desired cleaning and debris retention characteristics. Furthermore, the pattern of heat sealing can be varied from the pattern illustrated in the figures. For example, the heat sealing can be performed to define non-linear heat sealing regions. Furthermore, the heat sealing can be carried out to form words or trademarks indicative of the source of the scrub sponge. 

What is claimed is:
 1. A scrub sponge comprising a sponge having a top surface, a bottom surface and a periphery extending around said sponge between said top and bottom surfaces, a scrub layer having a top surface, a bottom surface and a periphery extending around said scrub layer between said top and bottom surfaces, said top surface of said scrub layer being disposed in substantially face-to-face relationship with said bottom surface of said sponge, said periphery of said scrub layer being substantially registered with said periphery of said sponge, the scrub layer being fused to the sponge completely around the registered peripheries of the scrub layer and the sponge and at a plurality of spaced apart locations inwardly from the registered peripheries of the scrub layer and the sponge.
 2. The scrub sponge of claim 1, wherein the sponge is formed from a polyester foam.
 3. The scrub sponge of claim 2, wherein the scrub layer is formed from a reticulated filter foam.
 4. The scrub sponge of claim 3, wherein the reticulated filter foam is a reticulated polyurethane foam.
 5. The scrub sponge of claim 4, wherein the reticulated polyurethane foam has approximately 20-30 pores per inch.
 6. The scrub sponge of claim 5, wherein the reticulated polyurethane foam has a density of approximately 1.4 lb/cu. ft.
 7. The scrub sponge of claim 6, wherein the reticulated polyurethane foam has a tensile strength of approximately 18-20 psi.
 8. The scrub sponge of claim 7, wherein the reticulated polyurethane foam has a tear strength of approximately 5.0 lb./inch.
 9. The scrub sponge of claim 1, comprising a peripheral seam extending entirely around the substantially registered peripheries of the scrub layer and the sponge and corresponding to areas where said periphery of said scrub layer and the periphery of said sponge are fused, the peripheral seam having a width of approximately 0.8-0.15 inch.
 10. The scrub sponge of claim 1, wherein areas of the scrub layer fused to said sponge inwardly from said registered peripheries define a grid pattern of fusing, said grid pattern of fusing including a plurality of fused lines, each of said fused lines extending to two spaced apart locations on the periphery of said scrub layer.
 11. The scrub sponge of claim 10, wherein the fused lines define regions on said bottom surface of said scrub layer spaced upwardly from portions of said bottom surface of said scrub layer adjacent said fused lines, such that said fused lines define areas of said scrub sponge for collecting debris removed by said scrub layer.
 12. The scrub sponge of claim 1, wherein a distance between said top and bottom surfaces of said sponge exceeds a distance between said top and bottom surfaces of said scrub layer.
 13. A scrub sponge comprising: a sponge formed from a soft polyester foamed material and having a top surface, a bottom surface and a periphery extending around said sponge and between said top and bottom surfaces; and a scrub layer formed from a reticulated polyurethane foam and having a top surface, a bottom surface and a periphery, said top surface of said scrub layer being disposed in substantially face-to-face relationship with said bottom surface of said sponge, said periphery of said scrub layer being substantially registered with said periphery of said sponge, regions of said scrub layer adjacent the periphery thereof being fused to regions of said sponge adjacent the periphery thereof, said scrub layer and said sponge further being fused to one another along a plurality of fused lines disposed inwardly from the peripheries of said scrub layer and said sponge, said fused lines defining a plurality of recesses offset from portions of said bottom surface of said scrub layer adjacent said fused lines, whereby said recesses define regions of said scrub sponge for trapping and retaining debris removed during use of said scrub sponge.
 14. The scrub sponge of claim 13, wherein the fused lines define a grid pattern formed on said bottom surface of said scrub layer.
 15. The scrub sponge of claim 14, wherein each said fuse line intersects at least one other of said fuse lines. 